Drilling machine



June 6, 1961 F. H. MUELLER ErAL 2,986,958

DRILLING MACHINE Origlnal Filed Nov. 15, 1956 6 Sheets-Sheet 1 IlI/Illll INVENTORS FRANK H. MUELLER JOHN J. SMITH ATTORNEYS June 6, 1961 F. H. MUELLER ET AL 2,986,958

DRILLING MACHINE Origlnal Filed Nov. l5, 1956 6 Sheets-Sheet 2 Fm. 2. 52 a INVENTORS 2o FRANK H. MUELLER JOHN J. SMITH ATTORNEYS June 6, 1961 F. MUELLER ErAL 2,986,958

DRILLING MACHINE Origlnal Filed Nov. l5, 1956 FGJ.

6 Sheets-Sheet 3 Y INVENTORS FRA N K H. MUEL LER J OH N J. S M IT H ATTORNEYS June 6, 1961 F. H. MUELLER ETAL DRILLING MACHINE Original Filed Nov. 15, 1956 6 Sheets-Sheet 4 INVENTORS FRANK H. MUELLER JOHN J. SMITH ATTORNEYS June 6, 1961 F. H. MUELLER ET AL 2,986,958

DRILLING MACHINE Original Filed Nov. l5, 1956 6 Sheets-Sheet 5 22e h 284 v 226 262 so 266 Q 260 286 als 26B 22o 256 27s 25s 23e l j n 2,4/ 25m 244 f 280Y 27e 25o i 216 si 274 4 54 |42 l 26 FIG 13 24 262 258 l l 5 272 6e so 246/ e2 76 so FIGJO.

INVENTORS FRANK H. MUELLER JOHN J. SMITH 204 BYMW, uw

ATTORNEYS June 6, 1961 F. H. MUELLER ErAL 2,986,958

DRILLING MACHINE Origlnal Filed Nov. l5, 1956 6 Sheets-Sheet 6 INVENTOR S FRANK H. MUELLER JOHN J. SMITH WMM gu/VMM) ATTORNEYS Unit rates 3 Claims. (Cl. 77-37) This invention relates to enclosed drilling and tapping machines of the type employed to cut an opening in a wall of a fluid chamber, thread and cut opening, and screw into the tapped opening a fitting, such as a valve body or a service T for connecting a branch line to the fluid chamber. Such operations are customary, for example, in attaching lateral or service connections to a fluid conduit, such as a water or a gas main, While the latter is in service.

In particular, this invention pertains to improvements in machines of the type disclosed in U.S. Patents Nos. 2,291,979 and 2,745,669. This application is a division of our copending application Serial No. 622,470, led November 15, 1956.

The machines disclosed in the aforementioned patents, while outstandingly successful for their intended purposes, are susceptible of improvements to facilitate their operation.

Thus, it has been found desirable to improve the connection between the boring bar of the machine and the tool carried thereby. The objects of such improvement are to provide a construction wherein no special tools are required to secure the tool to the end of the boring bar, and wherein such construction facilitates the ready attachment or detachment of tools. A particular object of such improvement is to provide a construction wherein a tool, known as a stop carrier, can be positively detached from the bar without opening the machine or removing the bar therefrom.

In previous machines of the type under consideration, the boring bar is fed by the manual rotation of a feed collar that is threadedly engaged with a fixed part of the machine and has a yoke pivotally connected thereto for swinging movement into and out of engagement with a shoulder on the boring bar. In actual practice, it has been found that occasionally the yoke tends to slip off such shoulder on the boring bar, with the consequent annoyance and delay of having to back up the feed collar and re-engage the yoke. Hence, it is another object of this invention to correct this deficiency.

In present-day machines of the type under consideration, the boring bar normally is driven manually by a ratchet wrench, but in the improved construction under consideration here, it is desirable to provide an improved ratchet wrench which not only may be utilized to drive the boring bar by hand, but also may be used to facilitate the attachment and detachment of tools to and from the boring bar. Hence, it is another object of this invention to provide such an improved wrench.

Additionally, as previously stated, the boring bars of the machines of the type under consideration substantially always have been driven by hand, by means of a ratchet wrench. The manual drive of a boring bar, however, becomes quite fatiguing and time-consuming when drilling operations are being performed, although the tapping operation, after an opening has been cut in the main, may be accomplished quite readily by hand without undue fatigue or consumption of time. Accordingly, it is still another object of this invention to provide a power driven attachment for a drilling machine of the type under consideration, which attachment may be used to provide both arent ice a power drive and an automatic feed for the boring bar during drilling operations.

Numerous other objects and advantages of the invention will become apparent from the following description and accompanying drawings in which:

FIGURE 1 is a central, vertical, sectional view of a tapping machine embodying this invention. The machine is shown attached to a main and with the parts in their position at the termination of a tapping operation.

FIGURE 2 is an enlarged, fragmentary perspective view of the machine shown in FIGURE l.

FIGURE 3 is an enlarged, fragmentary view of the tool-carrying end of the boring bar of the machine shown in FIGURE 1.

FIGURE 4 is a sectional view taken substantially on line 4-4 of FIGURE 3.

FIGURE 5 is an enlarged, sectional view with parts broken away to illustrate details, taken substantially on line 5-5 of Figure 1,

FIGURE 6 is an enlarged, fragmentary view, partly in vertical section, of the machine shown in FIGURE l and illustrating the construction of the ratchet wrench and its attachment to the machine.

FIGURE 7 is a plan View taken substantially on line 7--7 of FIGURE 6.

FIGURE 8 is a sectional view taken substantially on line 8--8 of FIGURE 6.

FIGURE 9 is a fragmentary, plan view of the chain yoke shown in FIGURES l and 2.

FIGURE 10 is an enlarged, fragmentary, sectional view taken substantially on line 10--10 of FIGURE 9.

FIGURE 11 is an enlarged, fragmentary view, partly in vertical section, illustrating the use of a stop carrier, embodying this invention, for atta-ching a corporation stopl to a main.

FIGURE l2 is a sectional view taken substantially on line 12-12 of FIGURE 11 and additionally illustrating, in fragmentary View, a special type wrench engaged with the stop carrier for disconnecting the latter from the stop.

FIGURE 13 is a central, vertical, sectional view taken substantially on line 13--13 of FIGURE 14 of a combined power drive and automatic feed -attachment for the drilling machine shown in FIGURE l and showing such attachment connected to the machine.

FIGURE 14 is a top plan View of the attachment shown in FIGURE 13.

FIGURE 15 is a bottom view of the attachment shown in FIGURE 13.

Referring now to the drawings, there is shown in FIG- URES 1 and 2 a curved wall chamber, such as a gas or water main 20, having mounted thereon the usual saddle 22 with a gasket 24 interposed therebetween. The saddle 22 has an opening therethrough that is counterbored at its outer end to receive the lower open end of a op' valve housing 26. A gasket 28 is interposed between the saddle 22 and the housing 26.

The housing 26 is hollow and bulges outwardly at one side thereof to form a lateral enlargement 3) for the reception of a op valve 32 when the latter is in its open or inoperative position, as best shown in FIGURE l. The flop valve 32 is carried on a shaft 34 journalled in the walls of the housing 26 and provided with an exterior handle 36 to move the valve into or out of engagement with a valve seat 3S in the housing, to either close or open the valve. The open upper end of the flop valve housing 26 is interiorly threaded for connection of one end of a cylinder 40 which, together with the housing,- constitutes the barrel 42 of the machine. Preferably, a circumferential groove is provided in the housing 26 at the inner end of its threads, and an O-ring 44 is disposed in such groove for sealing engagement with a smooth-walled portion of the inner end of the cylinder aanwas 40. The upper open end of the cylinder 40 is provided with an interior reinforcing ring or band 46 and is closed by a threaded bonnet or cap `4S that is sealed to the cyllnder by an O-ring V50. Preferably, the cap' 48 is provided with radial handles S2 to facilitate its attachment and detachment to and from the cylinder 40. Thus, the barrel 42 and the cap 4S form an interior iluid chamber 54.

Projecting upwardly from the top of the cap 48 is an exteriorly threaded cylindrical bearing extension 56 of reduced diameter. The cap 48 and its extension 56 have an axial bore 58 which forms a bearing for and through which extends an axially and rotatably movable tubular boring bar 60. Adjacent its .ends the bore 58is provided with interior circumferential grooves having O-rings 62 therein for sealing engagement with the boring bar 60. Between these O-rings 62, the bore 58 is enlarged, as at 64, to provide considerable clearance between the bore and the boring bar v60 and form an annular chamber into which lubricant can be introduced through a charging opening that is normally closed by a screw plug 66. :The upper exterior end portion `68 of the boring bar 60 1s square, or of other noncircular formation, best shown in FIGURES 6 and 8, for reception in a complementary socket or opening 70 of a ratchet Wrench 72 that is used to rotate the bar by hand. For a short distance ybelow its square end portion 68, the boring bar 60 is reduced 1n diameter to provide a shoulder 74 facing the end portion. A thrust collar 76 is seated against the shoulder 74 and is held in place by a set screw 78.

A generally U-shaped yoke S0 has the ends of its legs or arms 82 pivotally carried by a feed collar 84 threadedly mounted on the extension 56. The base 86 of the yoke 80 has a generally U-shaped notch A88 therein, as best shown in FIGURE 5, so that the yoke may be swung up into the position shown in FIGURE l, wherein the boring bar 60 is received in such notch and the yoke base may bear against the top of the thrust collar 76. In such position, a feeding movement may be imparted to the bar 60 on rotation of the feed collar 84, which rotation can be accomplished manually by radial handles 90 thereon. Preferably, a nylon washer 92 is interposed between the thrust collar 76 and the base 86 to reduce friction therebetween. Projecting from one side of the notch 8S is a spring-pressed detent 94, best shown in FIGURE 5, that is spaced from the bottom of the notch a distance greater than one-half the diameter of the bar 60. Hence, in the operative position of the yoke `8), the detent 94 engages the bar 60 to retain the yoke in such position. Disposed about the notch 88 and extending upwardly from the base 86, the yoke 80 is provided with a souare. or other noncircularly-shaped, extension 96 (FIGURES 5, 6, and 13), the utility of which will be later explained. A bypass valve 98, mounted on the flop valve housing 26, is employed in the usual manner to control communication between the portions of the iluid chamber 54 above and below the op valve seat 38 when the valve 32 is closed, to facilitate both tight engagement of the valve with the seat and subsequent opening of such valve. The barrel 42 is held against the saddle V22 by a chain 100 extending about the main and having its opposite ends secured to the opposite forks 102 of a chain yoke 104 thatis engaged against an upwardly facing shoulder 106 on the barrel 42 formed by the upper end of the flop valve housing 26, as is best shown in FIGURES 1 and 2. The lower or forward end of the boring bar 60 has an enlarged tool holder 108 secured thereto, as by welding, as best shown in FIGURE 3, for removably carrying a tool, such as a combined drill and tap 110 (FIGURE l) or a stop carrier 112 (FIGURE 1l). Seated against an exterior rearwardly-facing shoulder 114 on the holder 108 is a cylindrical guide collar 116 of substantial diameter and preferably provided with a bearing surface of synthetic plastic 118 having high wear and abrasion resistant characteristics, such as nylon. The plastic 118 may be 1n the form of a sleeve molded onto the collar 116 and locked thereto by interior circumferential ridges extending into complementary exterior grooves, as at 120, in the metal portion of the collar. This guide collar 116 has a close t within an accurately-machined cylindrical interior guiding portion 122 (FIGURE l) in the flop valve housing 26, immediately above the valve seat 38, to main-` tain the tool properly centered at the start of a cutting operation or the carrier 112 properly centered with a tapped opening 124 (FIGURES l and ll) at the beginning of a stop-inserting operation. Thus, the guide collar 116 and the interior cylindrical portion 122 prevent any side shifting of the tool holder 108, during initial cutting or inserting operations, which might be occasioned by wear of the bar bearing portions of the bore 58 in the cap 48. After the opening has been cut and during the subsequent tapping operation, the guide collar 116 may pass inwardly beyond the flop valve seat 38, but during the tapping operation or completion of an inserting operation, it will be evident that no guiding of the bar 60 other than that provided by its bearing in the cap 48 is necessary. The exterior surface of the plastic 118 is tinted longitudinally, as at 125. The guide collar 116 also is provided with a reduced extension 126 which depends from or projects forwardly of such collar about the lower portion of the tool holder 108. The guide collar 116 may be retained on the tool holder 108 by a set screw 128 which passes through the extension 126 and is threaded into the tool holder. From the aforedescribed construction, it is evident that the uted formation of the plastic 118 provides a ready hand-hold for grasping the holder 108 to either rotate the boring bar 60 or retain it against rotation, for reasons later described. v- The holder 108 is provided at its lower or forward end with a' tapered socket 130 for receiving the correspondingly tapered shank 132 of either of the tools 110 and 112. Diametrically-opposed, arcuate recesses or notches 134 (FIGURE 3) are provided in the rim of the socket for reception of the projecting ends of a transverse driving pin 136 in the tool shank 132. The pin 136 is of a length equal to or slightly less than the maximum outer diameter of the holder 108. The end of the tool shank 132 is provided with a coaxial threaded socket 138, best shown in FIGURES 3 and l1, for engagement with the' threaded end of a draw rod 140 that extends rearwardly or upwardly completely through the boring bar 60. At its upper or rearward end, the draw rod 140 is provided with an enlarged noncircular, eg., hexagonal. head 142, as best shown in FIGURE 6. In the embodiment illustrated, such head 142 is formed by a nut threaded onto the upper end of the rod 140 and rigidly secured thereto, as by a pin 144. The underside of the head 142 is adapted to bear against athrust washer 146 seated against an interior shoulder in the upper end of the boring bar 60. From this construction, it will be seen that the tool shank 132 may be partially inserted into the socket 1.30 and threadedly engaged with the draw rod 140. Rotation or tightening of the latter by its head 142 will then serve to pull the shank 132 tightly into the socket 130 and position the ends of the pin 136 in the notches 134 in the rim of the socket. Thus, the draw rod 140 can securely but detachably retain the tools 110 or 112 in the holder 108. The inner end of the socket 130 in the holder 108 merges with a cylindrical portion 148 of somewhat greater diameter than the interior of the boring bar 6l), which terminates at its inner end in a forwardly or downwardly facing shoulder 150, best shown in FIGURE 3. Within the cylindrical portion 148 of the holder 108, the draw rod 140 is provided with an exterior cylindrical enlargement 152, substantially complementary to and for guiding engagement with the interior wall surface of the cylindrical portion. When the draw rod 140 is in secure retaining engagement with a tool, as shown in FIGURE 3, so that the rod head 142 bears against the washer 146, the enlargement 152 on the rod is spaced somewhat from the interior shoulder 150. The enlargement 152 on .the rod -140 is provided with an exterior circumferential groove having an O-ring 154 therein to provide a seal between the enlargement and the interior Iwall surface of the cylin- 'drical portion 148 of the holder. From this construction it will be seen that the enlargement 152 prevents loss or withdrawal of the draw rod 140 rearwardly through the boring bar 60, while the O-ring 154 prevents passage of any fluid from the chamber 54 rearwardly through the bar.

The ratchet Wrench 72 embodying this invention, and which is 'shown best in FIGURES 6, 7 and 8, comprises a main body 156 provided with a bore or bearing aperture 158 extending therethrough and a detachable operating handle 160 extending generally radially of such bore. On one side the body 156 is provided with a counterbore 162 for the reception of a ratchet wheel 164 having extended cylindrical hub portions 166 and 168 and the central noncireular aperture or socket '70 that is complementary to Iand for reception of the square end portion 68 of the boring bar 611. The hub portion 166 tits within the body bore 15S with its outer end substantially ush with the exterior surface of the body 156. A closure or retaining plate 172 is fastened to the other side of the body 156, as by screws 174, and has an annular rib or flange 176 fitting Within the counterbore 162 and bearing against one side of the wheel 164 to retain the latter in the body. The plate 172 is provided with a bore 178 in axial alignment with the body bore 158 but of somewhat greater diameter than the latter for journally mounting one end of a sleeve-like wrench member 180. At its one end the member 181) is provided with an exterior circumferential ange 1134 fitting within an interior enlargement 186 at the inner end of the bore 17 S in the -plate 172. Consequently, the wrench member 139 is rotatably retained in or swivelly connected to, the wrench 72. Within its one end, the member 13? is provided with a cylindrical socket 18S for journally receiving the hub portion 168 of the ratchet wheel 164. Beyond the socket 18S the member 180 is exteriorly and interiorly reduced and provided with a smaller, noncircular socket 190 complementary to the enlarged head 142 on the draw rod 14() and for Wrench engagement therewith. Secured to the reduced portion of the wrench member 189, as by a set-screw 191, is an er1- larged handle 192 to provide a ready hand-hold for manually turning the Wrench member. Mounted in a bore 194 in the body 156 extending radially of the wheel 164 is a reversible, spring-pressed ratchet pawl 196 engageable in the usual manner with notches 198 in the ratchet wheel, as best shown in FIGURE 8.

The chain yoke 1114, on one side therof, is laterally enlarged as yat 2110, and provided therein with an upwardly facing cylindrical socket 202, of a diameter only slightly greater than the maximum transverse dimension of the square end portion 65 of the boring bar 61)* and of a length substantially equal to such end portion, as best shown in FIGURES 9 and l0. The inner end or bottom of the socket 2112 is provided with a noncircular opening or socket 2114 that is complementary to the enlarged head 142 on the draw rod 141B for wrench engagement therewith. The function and purpose of the sockets will be explained later.

In use of the machine embodying this invention, after the barrel 42 has been secured in place on the main 20 and before the cap 4S is connected to the barrel, the boring bar 60 while carrying the cap and the yoke 81) is disposed in an inverted position and the square end portion 68 of the bar placed in the socket 2152 in the chain yoke 104 with the head 142 of the draw rod 140 engaged within the socket 204. The socket 2112 will support the boring bar 653 in this position while the shank 132 of the combined drill and tap 116 is partially inserted into the tool holder socket 130 and threadedly engaged with the adjacent end of the draw rod 140. rThereupon, by manually grapsing the guiding collar 116 on the tool holder 168, the boring bar 6i) can be rotated relative to the head 142 6 in a direction to tighten the threaded engagement between the draw rod 141) yand the tool shank 132.

After the tool 110` is thus firmly secured to the tool holder 10S, the boring bar 6@ is inserted into the upper end of the barrel 42 `and the cap 48 is threaded and tight'- ened onto the barrel. The boring bar 60 may then be pushed down manually until the tip of the tool 110 engages the main 20. Thereupon, the feed collar 84 is threadedly adjusted into a position wherein the yoke may be swung into detent-retained feeding engagement over the thrust collar 76 on the boring bar. The ratchet wrench 72 is then engaged with the square end portion 68 of the boring bar 6i) and operated, by hand, to rotate the latter so that the tool will drill a hole in the wall of the main 21). During this drilling operation, the feed collar S4 is rotated by hand to advance the tool 110 and provide the necessary laxiai force thereon to effect a cut in the main 2t). After the main 20 has been drilled by the forward drill portion of the tool 110, the following tapping portion of the tool will engage the main, and continued `operation of the ratchet wrench 72 will serve to tap the drilled opening in the main, as is best shown in FIGURE l. In this connection, it will be seen that force feed of the bar 6G during the tapping operation is not necessary because the too-l 110 is self-feeding during the tapping operation.

After the main 20 has thus been drilled and tapped, the yoke 80 is swung out of engagement over the collar 76 and the ratchet pawl 196 on the wrench 72 is reversed so that reverse operation of the Wrench will serve to unthread the tool 110 from the tapped opening in the main. Thereupon, the boring bar 60 is pulled up manually until the tool holder 108 and the tool 110 are completely received within the upper portion of the barrel 42 above the valve seat 38. The iiopvalve 32 can then be closed and the cap 48, together with the boring bar 60, removed in conventional fashion.y The boring bar 60 is again inverted and supported in the sockets 202 and 204 in the chain yoke 104, as aforedescribed, while the bar is manually rotated in a direction to unthread the draw rod from the tool 111i, whereby the latter can be removed. At this time, the stop carrier 112, best shown in FIGURE 1l, is secured in the socket 131) in the tool holder 108, in the same manner as aforedescribed for the attachment of the drill and tap 110 therein. The stop carrier 112 has a tapered shank 132, a threaded end socket 138, and a transverse driving or locking pin 136 identical to the corresponding portions of the drill and tap 110. In place of the drilling and tapping portions of the tool 110, how ever, the carrier 112 is provided, at its forward end, with an interiorly threaded socket 206 for the reception of one of the threaded nipples 208 of a corporation stop 210. This stop-carrying socket 206 of the carrier may be substantially identical to that illustrated and described in the above-mentioned Patent No. 2,745,669.

With the stop 210 closed, the cap 48, together with the boring bar 60, is re-attached to the barrel 42, after which the flop valve 32 is opened and the boring bar 60* advanced, either directly by hand or by the feed collar 84 and yoke Si), until the free other nipple 208 of the stop is engaged with the tapped opening in the main 20. At this time, the boring bar 611 is again rotated by the ratchet wrench 72 to screw the stop 210 into the tapped opening in the main 2t), as shown in FIGURE l. The handle of the ratchet wrench 72 may then be grasped by hand and rotated in a direction to unscrew the draw rod 140 from the stop carrier 112, while the bar 60 is held against rotation by grasping the wrench handle 160. In the event that the shank 132 of the carrier 112 sticks in the socket 130, after the rod 140 has been unscrewed a few turns and thereby lifts the rod head 142 olf the washer 146, because of the clearance between the enlargement 152 `and the shoulder 150, the head 142 can be tapped lightly to completely free the shank of the stop carrier from the socket in the tool holder. Thereupon, further unthread- 7 1 l ing rotation of the draw rod, accompanied by a slight retraction of the bar 60, will serve to completely detach the stop carrier 112 from the tool holder 108, so that the cap 48, together with the boring bar 60, can be removed from the machine, and the chain 100 detached so that the complete machine can be removed from the main 2t).

This operation will leave the stop 210, together with the carrier 112 threaded thereon, threadedly engaged in the main 20, as best shown in FIGURE ll. Thereupon, the stop 210 can be firmly tightened into the main 20, as by an appropriate wrench (not shown), and thereafter a special wrench 212, best shown in FIGURE l2, can be engaged with the stop carrier 112, while the latter is held by the aforementioned appropriate conventional wrench, to unthread the carrier from the stop and thus complete `the operation of installing the stop on the main. In this connection, it will be readily understood 4that a service T (not shown) can be installed on the main 28 in exactly vthe same manner -as that described for the installation of a corporation stop.

Referring now to FIGURES i3 to 15 of the drawings, there is shown an attachment for the drilling machine which will enable the bar 60 to be driven by power during the drilling operation and at the same time provide an automatic feed for the bar. The attachment includes a housing 214 having a somewhat dish-shaped main body 216 and a top cover 218, which may be secured to the body by screws 220 extending through flanged peripheries of the cover and body. Iournalled in a bearing portion 222 of the cover 218 and projecting into the housing 214 is a drive shaft 224 having a square, or other appropriate noncircular, outer end 226 projecting outof the cover for driven engagement by appropriate means (not shown). Immediately below its square outer end portion 226, the shaft 224 is threaded for the reception of a split clamping nut 228. Preferably, a washer 230 is interposed between the nut 228 and the exterior surface of the cover 218. The other end of the shaft 226 projects through a bearing portion 232 of the body 216 and is enlarged, as at 234, to form a shoulder 236 thereon facing the inner side of the cover 218. Formed in the end of the enlarged shaft portion 234 is a socket 23S that is exposed to the exterior of the housing 214 and is of the same length as and complementary to the noncircular end portion 68 of the boring bar 60 for driving engagement therewith. The bottom of the socket 238 is provided with a circular recess or socket 240 of slightly larger diameter than the major transverse dimension of the rod head 142 for free rotative reception thereof.

Iournalled in the bearing portion 232 of the body 216 is a tubular yoke-driving sleeve 242 that is rotatably mounted on the enlarged portion 234 of the shaft and has an interior circumferential flange 244 at its inner end which overlies the shoulder 236 on the shaft 244. Preferably, an anti-friction bushing 246 is interposed between the sleeve 242 and the shaft 224 in order to facilitate free rotation therebetween. The sleeve 242 projects outwardly beyond the enlarged end 234 of the shaft and is provided therebeyond with an interior configuration or socket 248 of the same length as and complementary to the extension 96 on the base 86 of the yoke 88 for driving engagement therewith.

Within the housing 214 a large gear 250 is mounted on the sleeve 242 and secured thereon, as by a key 252, with one side of its hub portion bearing against the inner surface of the housing body. A smaller gear 254 is secured to the shaft 224 within the housing 214, as bya key 256, and at one side bears against the inner surface of the cap 218. Interposed between the inner end of the sleeve 242 and the gear 254 is a spacer washer 258 which also overlies and bears against the hub portion of the gear 250. From the foregoing construction, it will be seen that the clamp nut 228, together with the gear 254, spacer washer 258, and sleeve flange 244, serves to retain the shaft 224 and the sleeve 242 against axial movegaseosa ment relative to the housing 214, while the housing body 216 and the spacer washer 258 likewise retain the gear 250 against such movement. Preferably, the bearing portions 222 and 232 of the housing 214 are provided with interior circumferential grooves having O-rings 260 and 262 therein to serve as oil seals, while the enlarged portion 234 of the shaft has an exterior circumferential groove having an O-ring 264 therein to provide a seal between the enlarged shaft portion and the bushing 246. The housing 214 may be iilled with oil through a lling opening normally closed by a threaded closure plug 266.

Journalled in appropriate, aligned bearing sockets 268 and 270 formed in the interior surfaces of the cover 218 and the body 216, respectively, is an idler shaft 272 otset from the drive shaft 224. A small gear 274 integral with the shaft 272 meshes with the large gear 250. A larger gear 276 is secured to the shaft 272, as by a key 278, and has the opposite sides of its hub portion bearing against the interior surface of the cover 218 and a shoulder 280 on the idler shaft 272, respectively. The gear 276 meshes with the smaller gear 254 on the shaft 224. From the foregoing construction, it will be seen that the gears 254, 276, 274 and 250 constitute a reduction drive for driving the sleeve 242 at a speed less than that of the shaft 224. The gear ratios are such that when the attachment is in use, as later described, the boring bar will be fed at a rate appropriate for a drilling operation.

On the upper side of the cover 118 is an upstanding lug 282 provided with a transverse bore 284 for the reception of a pivot pin (not shown) that can be retained in such bore by a thumb screw 236. This arrangement may serve to pivotally support a motor holder (not shown) on the attachment. Such motor holder may bc of the type illustrated in United States Patent No. 2,651,- 222. In general, such holder may serve to properly position and hold an air motor (not shown) in position for driving engagement with the outer end 226 of the shaft 224.

in use, the attachment is positioned on top of the boring bar 68, with the yoke in its feeding position, and manipulated until the upper square end portion 68 of the bar is received, at least partially, in the socket 238 of the attachment. In the event that both sockets 238 and 248 of the attachment are not correctly oriented with respect to the end 68 of the boring bar and the projection 96 on the yoke, the latter can be rotated slightly by hand until the yoke projection becomes properly laligned with the socket 248 in the sleeve 242. At this time, both of the sockets 238 and 248 of the attachment will properly receive and drivingly engage the end 68 of the boring bar and the projection 96 on the yoke, respectively. The motor holder and its motor (not shown), or other type of power drive, can then be fastened to the attachment, and the motor can be operated to drive the shaft 224 to thereupon drive the boring bar 60 to drill a hole in a main. At the same time, it will be seen that the yoke 88 will be driven at a rate of speed less than that of the boring bar 60. This rate of rotation of the yoke 80 serves to rotate the collar 84 to feed the boring bar 60 automatically at a rate appropriate for `a drilling oper-ation.

It will be evident that this power drive of the bar 6G, together with the automatic feed thereof, will greatly reduce the time necessary for an operator to initially drill a main as well as greatly reduce the time necessary to complete such drilling operation. After the main has been drilled by power, the attachment can be removed and the wrench 72 used to rotate the boring bar 60 for the tapping operation. In this connection, it is well known that a tapping operation can be carried on quite rapidly and with considerably less effort required than for a drilling operation.

It thus will be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing specific embodiment has been shown and described only for the purpose of illustrating the principles of this invention and is subject to extensive change without departure from such principles. Therefore, this invention includes all modiications encompassed within the spirit and scope of the following claims.

We claim:

1. A wrench engageable with the non-circular end of a tubular boring bar and with the noncircular head of a draw rod extending through the bar, with the head being smaller, than the bar end and disposed exteriorly of and adjacent to the end of the bar, comprising: a handled body; a ratchet wheel rotatably mounted in said body; a ratchet pawl mounted in said body and engageable with Said wheel; means defining a central, noncircular opening in said wheel complementary to and for reception of the bar end; and a member swivelly connected to Said body coaxially of said wheel, said member having a portion disposed beyond one end of said wheel opening and provided with a central noncircular opening coaxial with said wheel opening and complementary to and for reception of the draw rod head, whereby relative rotation between the bar and rod can be effected by relative rotation between said body and said member.

2. The structure defined in claim 1 in which the member has a portion disposed exteriorly of the body and noncircular in transverse section to facilitate manual rotation of said member.

3. A wrench engageable with the noncircular end of a tubular boring bar and with the noncircular head of a draw rod extending through the bar, with the head being smaller than the bar end and disposed exteriorly of and adjacent to the end of the bar, comprising: a handled body; a ratchet wheel having reduced hub portions journalled in said body; a ratchet pawl mounted in said body and engageable with said Wheel; means dening a noncircular opening extending coaxially through said wheel and complementary to and for reception of the end of the bar; a member having a sleeve-like portion interposed between one of said hubs and said body and swivelly connected tothe latter; and means dening a non-circular opening in said member beyond the end of said one hub and coaxial with said wheel opening, said member opening being complementary to and for reception of the draw rod head for rotation of the latter by manual rotation of said member.

References Cited in the le of this patent UNITED STATES PATENTS 2,777,341 Marchant Jan. l5, 1957 

